The International ­Olympic Committee has confirmed that two boxers who were disqualified from the world champion­ships last year for failing gender eligibility tests will be allowed to fight in Paris.

Imane Khelif of Algeria and Lin Yu‑ting of Chinese Taipei (Taiwan) both start their Olympic campaigns this week: Khelif will meet the Italian Angela Carini in the 66kg ­cate­gory, and Yu-ting is expected to face an unnamed opponent in the 57kg cate­gory on Friday.

The IOC’s decision will be contro­versial, with the former world champion Barry McGuigan expressing his unease. In a post on X, he wrote: “It’s shocking that they were ­actually allowed to get this far, what is going on?”

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The situation has arisen because the world championships last year was run under the auspices of the International Boxing Association, whose president, Umar Kremlev, told the Russian news agency, Tass, that DNA tests had “proved they had XY chromosomes and were thus excluded from the sports events”.

The IBA told the Guardian it had made the decision “following a comprehensive review and was intended to uphold the fairness and integrity of the competition”.

Since then, however, the IBA has been banned from running the Olympic boxing tournament in Paris because of long-running questions surrounding governance issues and a series of judging scandals. That means the boxing in Paris is now being run under the auspices of the IOC’s Paris 2024 Boxing Unit, which has more relaxed rules than the IBA.

In a statement the IOC said: “The PBU used the Tokyo 2020 ­boxing rules (enforced at the Olympic Games Tokyo 2020 and the related quali­fying tournaments) as a baseline to develop its regulations. Those rules descended from the Rio 2016 rules. The PBU endeavoured to restrict amendments to minimise the impact on athletes’ preparation and guaranteeing consistency between Olympic Games.”

However the IOC’s own MyInfo website acknowledges that both boxers failed gender eligibility tests last year.

In its internal system, which is provided to journalists in Paris, the IOC states that Khelif was “disqualified just hours before her gold medal showdown against Yang Liu at the 2023 world championships in New Delhi, India, after her elevated ­levels of testosterone failed to meet the eligibility criteria”. The IOC also acknowledges that Yu-ting was “stripped of her bronze medal after failing to meet eligibility requirements based on the results of a biochemical test.

Yu-ting does not appear to have spoken about the situation. However the Agence France-Presse reported that Khelif claimed to be the victim of a “big conspiracy” after being disqualified just before the final at last year’s world championships.

“People have conspired against Algeria so that its flag doesn’t get raised and it doesn’t win the gold medal,” the 25-year-old said.

Rules regarding who should compete in the female category have been hotly contested in recent years. But there has been less debate about combat sports, where the risk of serious injury and even death is far higher. Scientific research has also found that the average punching power is 162% greater in those who have gone through male puberty compared to females.

Both countries’ Olympic committees have been approached for comment.